As for the third number on the release version
Panoramix2# pkg_add ettercap-NG
pkg_add: Warning: package `ettercap-NG-0.7.3nb5' was built for a platform:
pkg_add: NetBSD/i386 5.1 (pkg) vs. NetBSD/i386 5.1.2 (this host)
I guess these warnings are useless, right?

Yes. You are right.
Such warnings should definitely be fixed.
The real fix is system-dependent, though.
On Linux, for example, kernel version doesn't matter at all.

I wondered we may define default acceptable patterns,
for example, NetBSD:
ABI_COMPATIBLE_VERSION?= ${OS_VERSION:C/([0-9]*\.[0-9]*).*/\1/}*
PKG_ACCEPTABLE_PLATFORM?= ${OPSYS}-${ABI_COMPATIBLE_VERSION}-${MACHINE_ARCH}
Then, we can additionally put following pkg's Makefile currently depending on
pkgtools/osabi:
PKG_ACCEPTABLE_PLATFORM= ${OPSYS}-${OS_VERSION}-${MACHINE_ARCH}
For document only packages:
PKG_ACCEPTABLE_PLATFORM= *-*-*
Of course, PKG_ACCEPTABLE_PLATFORM must be included in binary package, and
package
related tools must handle it properly.
--
OBATA Akio / obache%NetBSD.org@localhost